From Burton: Similar to the hoodie version, the men’s Burton [ak] Piston Crew delivers precise core regulation when hiking for lines, slaying untracked pow, or getting deep into the backcountry. PolartecÒ Power StretchÒ Pro fabric has become legendary for warmth, breathability, mobility, and durability. A kangaroo pocket and welded bicep pocket stash essentials, while ergonomic seams and four-way stretch properties make this mid-layer as comfortable as it is versatile.